What is the difference between ArrayList and Vector? which one is better in Java

http://www.tutorialspoint.com/listtutorial/Difference-between-ArrayList-and-Vector-in-java/4680

You should normally use ArrayList - it offers better performance. Vector has just one "advantage" - it is synchronised for concurrent modification. But it turns out that this feature isn't very useful - if you are writing concurrent code, you typically need to lock at a much higher level of granularity than an individual collection class. As a result, Vector is often considered deprecated nowadays.